Hello,
Christine here from the Shopify Guru team - thanks for reaching out!
In the Shopify App store, we have an app called Locksmith which allows you to create a password for certain collections, products, and pages. This app is often used when a store shares both retail and wholesale selling environments.
If you are using a Shopify developed theme, you can follow a document from our knowledge base which allows you to create a template for products that would be for a pre-sale as opposed to Add to cart and purchased immediately.
The only challenge that may arise from having a retail and wholesale shop functioning in one store may be that you are only able to create one type of transaction process type at a time. If you wanted to only authorize a transaction as opposed to process the card immediately, currently you are only able to choose to process payments one way or the other. For this reason, many merchants will have two separate shops, one for retail and another for wholesale selling.
Here is some further information on ways you can sell Wholesale in your Shopify store: https://help.shopify.com/manual/products/discount-codes/offer-wholesale-prices
Let us know if you need anything else. We are just a click away!
Cheers,
Christine
Shopify Guru